Compound sentence (linguistics)

In grammar, clause structure refers to the classification of sentences based on the number and kind of clauses in their syntactic structure. Such division is an element of traditional grammar.

A simple sentence consists of only one clause. A compound sentence consists of two or more independent clauses. A complex sentence has at least one independent clause plus at least one dependent clause. A set of words with no independent clause may be an incomplete sentence, also called a sentence fragment.

A sentence consisting of at least one dependent clauses and at least two independent clauses may be called a complex-compound sentence or compound-complex sentence.

Sentence 1 is an example of a simple sentence. Sentence 2 is compound because "so" is considered a coordinating conjunction in English and sentence 3 is complex. Sentence 4 is compound-complex (also known as complex-compound). Example 5 is a sentence fragment.

The simple sentence in example 1 contains one clause. Example 2 has two clauses (I don't know how to bake and I buy my bread), combined into a single sentence with the coordinating conjunction so. In example 3, I enjoyed the bananas is an independent clause, and that you bought for me is a dependent clause; the sentence is thus complex. In sentence 4, The dog lived in the garden and the cat lived inside the house are both independent clauses; who was smarter is a dependent clause. Example 5 features a noun phrase but no verb. It is not a grammatically complete clause.

A simple sentence structure contains one independent clause and no dependent clauses.

This simple sentence has one independent clause which contains one subject, I, and one predicate, run.

This simple sentence has one independent clause which contains one subject, girl, and one predicate, ran into her bedroom. The predicate is a verb phrase that consists of more than one word.

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